1. Field of Endeavor
The present invention relates to optical amplification and more particularly to an optical parametric amplifier system.
2. State of Technology
U.S. Pat. No. 5,400,350 for a method and apparatus for generating high energy ultrashort pulses to Almantas Galvanauskas, issued Mar. 21, 1995 provides the following background information, xe2x80x9cBoth semiconductor sources (e.g., diode) and fiber sources are known which can produce ultrashort energy pulses having sub-picosecond pulse durations. Although these energy sources can provide reliable, robust operation in a compact, cost-effective manner, their inability to produce pulse energies comparable to those of large frame solid-state sources has limited their practical use.xe2x80x9d
U.S. Pat. No. 2002/0001321 for an ultrashort-pulse laser machining system employing a parametric amplifier to Michael D. Perry, published Jan. 3, 2002 provides the following background information, xe2x80x9cBulk optical parametric amplifiers have not been considered to date for moderate to high average power, ultrashort-pulse applications. The present optical parametric amplifier system does not rely on quasi-phase matching and can achieve both high average power and high gain for broad bandwidth chirped-pulses from a single or double stage system. By relying on parametric conversion rather than conventional laser amplification, there is no residual energy left within the gain medium. As a result, there are negligible thermal gradients and hence, one eliminates the depolarization and pulse distortion problems that severely impact the pulse quality and electrical to optical conversion efficiency of high average power ultrashort-pulse lasers. In addition to eliminating many of the thermal management problems associated with the high gain amplifier, the use of a parametric amplifier enables the production of the necessary ultrashort duration pulses from a simplified and more compact system. The pulses exiting the parametric amplifier may be compressed directly and used for machining or surgery or may be further amplified in a conventional laser amplifier to provide additional pulse energy before compression.xe2x80x9d
Features and advantages of the present invention will become apparent from the following description. Applicants are providing this description, which includes drawings and examples of specific embodiments, to give a broad representation of the invention. Various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this description and by practice of the invention. The scope of the invention is not intended to be limited to the particular forms disclosed and the invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
The present invention provides a system for producing an increased power coherent optical pulse. A first optical parametric amplifier and at least one additional optical parametric amplifier are provided. A first pump pulse and a signal pulse are injected into the first optical parametric amplifier producing a first amplified signal pulse from the first optical parametric amplifier. At least one additional pump pulse and the first amplified signal pulse are injected into the at least one additional optical parametric amplifier producing an output that results in the increased power coherent optical pulse. In an embodiment of the present invention, at least a second additional optical parametric amplifier is provided. At least a second additional pump pulse is injected into the at least a second additional optical parametric amplifier and at least a second additional signal pulse is injected into the at least a second additional optical parametric amplifier producing an output that results in the increased power coherent optical pulse. One embodiment of a system constructed in accordance with the present invention includes a first optical parametric amplifier, at least one additional optical parametric amplifier, a source of a first pump pulse that is direct into the first laser optical parametric amplifier, a source of a signal pulse that is direct into the first optical parametric amplifier, a source of at least one additional pump pulse that is direct into the at least one additional optical parametric amplifier, and a source of at least one additional signal pulse that is direct into the at least one additional optical parametric amplifier.
The invention is susceptible to modifications and alternative forms. Specific embodiments are shown by way of example. It is to be understood that the invention is not limited to the particular forms disclosed. The invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.